Process of expelling gases from metals.



r TM train stra a are;

rib.

WALTER S. ROCKEY AND HILLIABY ELDRIDGE, 0F YORK, N. Y.

PROCESS EXPELLING GASES FROM METALS.

979,24lsl. No Drawing.

T 0 all whom it may concern:

Be it known that we, \Vsnrnn S. B-QCKEY and Hrnnranr 'Enonmon, citizensof the United States, residing at New York city, in the county of NewYork and State of New Y ork, have invented certain new and usefulImprovements in Processes of Expellmg 'Gases from Metals, of which thefollowing is a full. clear, and exact specification.

Our invention relates to the preparation of metals or their alloys forplating, welding or casting.

It particularly relates to the expulsion of absorbed or occluded gases,from metals or their alloys which gases, as is Well known, are theprincipal cause of the forming-of cavities in and the porosity ofcastings, and

' welds, and uncovered sections or spots on the surfaces of wares platedby hotprocesses.

The first step in the preparation of the metals or their alloys for thepurposes spccitied above. is to thoroughly clean the metal or alloywhich is to be fused, of all oxid or oxids. This is absolutelynecessary, palticularly so in the'casc of copper or an alloy of copper,for copper and its alloyspossess the property of absorbing gases veryfreely when melted and in a liquid state. The reason in thisconnectionfor removing the oxid is that after the copper or its alloy is meltedunder a flux, the oxid is dissolved or mixed with the flux, and isdisseminated throughout its mass. Should iron for example be nowimmersed through the flux and into the molten copper or copper alloy tobe plated or welded, the oxygen of the copper oxid immediately combineswith the iron, form-' ing iron oxid and releasing atoms of-copper, or ifan alloy of copper and zinc is used, the copper is freed, iron oxid isformed, while the Zinc of the alloy immediately attacks the iron oxidwhich has been formed, thus forming zinc oxid and freeing iron. Should asteel article be immersed instead of iron, these reactions are increasedby the carbon of the steel assisting inthe reduction of all the oxidswhich were present infthe beginning, and have been formed afterward, andthereby evolving carbon monoxid gas. These reductions and combinationscause a continuous turmoil and bubbling in the mass and set up a highthermit temperature which always prevents good plating or Welding, andit canreadily be seen that to carry out the expulsion of gases fromcopper and Specificationf'of Letters Patent.

Patented Dec. 20, 1910.

Application filed March 21,1910. Serial No. 550,720.

fused for the purpose of producing nonporous thoroughly covered platingsor Welds, and solid non-p'orous casting; that the first step to be takento expel gases from metals would be to prevent the formation of as muchgas as possible, so as to prevent any reabsorption of gases by thecopper or its alloys or other metals after the contained gases have beenexpelled. This removal of the oxids can be done in various Ways byalkalies or acids, but we preferably remove these oxids or foreignmatter by abrasion, or byimmersing the metal in a suitable cleaningflux, which we find are the only thorough methods for removing oxid oroxide or foreign matter from metals, as suboxids or other oxids alwaysform again to a lesser degree after alkalies' or acids. are used.

A suitable non-gas containing flux, or a flux that will not generate gaswhen the metal to be treated is melted underneath the flux, or when theflux comes in contact with the metal that is immersed through said fluxinto the molted metal beneath said flux,

while being plated or welded, such as the fluxes composed of borontrioxid, the constitutional water from which has been eliminated, Whidhis melted in a suitable crucible, or other suitable melting device orreceptaole; the metal or alloy which has been cleansed is then placed'inthe crucible, and sinks rapidly beneath the surface of the melted flux;the temperature is then regulated to just above the melting point of themetal or alloy; this temperature is maintained until the metal or alloyis thoroughly melted and liquid, the temperature is then lowered untilthe metal or alloy sets or becomes solid again; wliile the flux at thistemperature remains liquid, and the metal on regaining itssolid state,evolves its contained gases .by molecular compression; these gases passout of the metal or alloy and bubble upward through and out of theliquid flux. This operation should be repeated until all gases areeliminated which is denoted by the cessation of all bubbles in the flux.After the expulsion of these gases, the temperature is again raised tojust above the melting point of the metal, or alloy and maintained untilit is again-fused and liquid. It is then ready for casting or may beused for plating other metals, and will be found to be non-porous andfree of gases, for on'account of being covered with ring a suitable fluxcontaining boron trioxid alloys free of gases consisting in repeatedlysorb any more gas after evolving its conalloys free of gases consistingin first re tained gases, it being a Well known fact that the metalsabsorb gases in their melted state and evolve them when cooling to asolid state, therefore if melted under a protecting covering ofnon-gaseous flux that contains no gases, and then cooled until solidenough to evolve its contained gases, it Would not be possible for themetal or alloy to absorb any more gases on account of said protection ofsaid non-gaseous flux.

Having thus described our invention, What We claim as new and desire tosecure by Letters Patent is:

1. The process of making copper or its alloys free of gases consistingin first heatto a molten state, then heating the metal beingtreated'above its'melting point heneath the said flux and then coolingsaid metal to a predetermined degree to cause the gases containedtherein to be expelled therefrom into said flux.

2. The process of making metals or metal heating the metal above itsmelting point beneath the surface of a suitable flux and then coolingsaid metal to a predetermined degree to cause the gases containedtherein to be expelled therefrom into said flux.

3. The process of making metals or metal alloys free of gases consistingin repeatedly heating the metal above its melting point beneath thesurface of a suitable flux, and then cooling said metal to approximatelyits melting point to cause the gases contained therein to be expelledtherefrom into and through said flux.

l. The process of making metals or metal alloys free of gasesconsisting'in repeatedly heating the metal above its melting pointbeneath the surface of a suitable flux, and then cooling said metal to asolid condition to cause the gases contained therein to be expelledtherefrom into and through said flux.

' 5'. The process of making metals or metal 1 moving the oxide orforeign matter from the metal and then fusing the metal beneath thesurface of a suitable flux, then cooling said metal to a predetermineddegree, to

cause the gases held therein to beexpelled from said metal into andthrough said flux.

6. The process of firstremoving the oxids or foreign matter from copperor copper alloy, then fusing said metal and protecting the same beneaththe surface of a flux of boron trioxid, and then solidifying the metalbeneath the surface of said flux to cause the gases containedtherein't-o be expelled therefrom into said flux.

7. The process of making copper or-its alloysfree of' gas consisting inrepeatedly heating the metal above its melting point heneath the surfaceof a flux of boron trionid, and then cooling said metal to apredetermined degree to cause the gases contained therein to be expelledtherefrom into said flux.

8. The process of making copper or its alloys free of gases consistingin repeatedly heating the metal above its melting point beneath a fluxof boron trioxid, and then cooling said metal to approximately itsmelting'point to cause the gases contained therein to be expelledtherefrom into and through said flux.

9. The process of making copper or its alloys free of gases consistingin repeatedly heating the metal above its melting point beneath a fluxof boron trioxid, and then cooling said metal to a solid condition tocause the gases contained therein to be expelled therefrom into andthroughv said flux.

In testimony Whereof, we afiix our signatures, in presence of twowitnesses, March 18th, 1910.

\VALTER S. ROCKEY. HILLIARY ELDRIDGE.

lVitnesses G. SPINK, CATHERINE CAPUANO.

